Coal-mining machine



N. of L EVIN COAL MINING MACHINE Dec. 15, 1925.

Original Filed Oct. 1 1917 s sheets-snail @n aw E @N 1N VEN T OR.

Dec. 15, 1925- N. D. LEVIN COAL MINING MACHINE Original Filed Oct. 18, 1917 6 Sheets-Sheet 2 WNN 0421 I lz mvzozz. BY 06 WITNESSES ATTORNEY.

Dean 1925' Y N. D. LEVIN COAL MINING MACHINE Original Filed Oct. 18, 1917 6 Sheets-Sheet 5 I III/ l...

. 1 ENTOR WITNESSES: E 6: 7 J @m i m I ATTORNEY.

N. D. LEVIN COAL MINING MACHINE Dec. 15, 1925- Original Filed 001i. 18, 1917 6 Sheets-Sheet 4 Illlllllllllllll r I I ATTORNEY.

WITNESSES.-

ecu 1Z5, 3%25 N. D. LEVEN COAL MINING MACHINE Original Filed Oct. 18, 1917 6 s t s t 5 [N V T OR.

ATTORNEY.

' WITNESSES Dec. 15, 1925- N. D. LEVIN COAL MINING MACHINE 6 Sheets-Sheet 6' Original Filed Oct. 18, 1917 A'VVZZNTOR. 6% I v A 1 T ORNE Y.

W/T/VLSSLB ZZZ Patented Dec. 15, 1925.

UNITED STATES PATENT OFFICE.

NILS D. LEVIN, 0F COLUMBUS, OHIO, ASSIGNOR TO THE JEFFREY MANUFACTURING COMPANY, OF COLUMBUS, OHIO, ACORI PORATION-OFOHIO.

COAL-MINING MACHINE.

Application filed October 18,1917, Serial No. 197,291. Renewed April s, 1925.

' The present invention relates to coal mining machines of the class whichis adapted to completely sever blocks of material from the walls of the mine.

I am aware that numerous machines have been heretoforeproposed provided with cutting mechanisms whereby both horizontal and vertical kerfs have been simultaneously. cut in the mine Wall to completely sever blocks of material therefrom. In such earlier constructions the cutting mechanisms have been of such character that the machine could be fed only laterally. ac'rossthe face of the vein either in long sweeping curves, thereby severing a succession ofcrescent shaped blocks, or in straight lines approximately parallel to the coal face. In the latter case 'it has been necessary to form a free end to the coal face to permit of the cutting mechanism being advanced to the line of cutting. Such machines arenecessarily restricted to operation in relatively wide rooms or upon the long wall system and are not adapted to universal application.

It is the especial object of this invention to provide a machineof the class described provided with cutting mechanism adapted to be moved either inwardly or outwardly or laterally in either direction relative to the coal face tocompletely sever blocks of material from the body of the vein.

The devices by which I attain, this object are fully set forth in the following specification and illustrated in the accompanying drawings of which. 1

Fig. 1 is a general plan viewof the preferred embodiment of my invention.

Fig. 2 is a side elevation of the machine illustrated in' Fig. 1.

Fig. 3 is a fragmentary sectional view taken along the line 33 of Fig.-,1.

Figs. 7 and 8 are details of the clutch I shifting mechanism associated with the auxiliary transmission mechanism.'

Fig. v9 is an inverted plan view of the truck.

, Fig. '10 is a section along the line 10-1Q of Figs. 5 and 6 showing details of the auxiliary transmission mechanism.-

Fig. 11 isa diagrammatic development of the gearing of the auxiliary transmission mechanism.

. Fig..,12gis'.a vertical .section taken along the line 1212 of Fig. 1.

Fig. 13 is a section taken along ,the line 1 313 of Fig. 1.

Fig. 14 is a detail of. the-feed drum. Fig. 15 is a cross section of the loading conveyer.

Fig. 16 is a longitudinal sectional view of the forward end of the loading conveyer. Figs. 17 and 18 are diagrammatieelevational views showing the method of operating the machine.

- Fig. 19 is a diagrammatic plan view showing the method of operating the machine upon the room andpillar plan of. mining.

Figs. 20,-21, 22, and 23 are diagrammatic figures illustrating the method of operating the machinefor driving entries.

' Fig. 24 is-a diagrammatic-plan View illustrating the method of operating the machine upon the long wall system.

Like numeralsrefer to similar parts inthe several figures. v

Referring to the drawings,the numeral 1 represents a steel plate to the edges of which are secured the stiffening angles 2 and which is'otherwise reinforced to produce a rigid base frame upon which is mounted-the coal 7 cutting mechanism. Fixed'to the underside of the plate 1 are suitable journal boxes 3 and 4 in which are journaled the axles 5 and 6 having wheels 7 adapted to travel along the rails 8 of the mine track. The above desupport an extension platform 11 upon which is mounted the controller mechanism and which affords a convenient place for the operator to ride while the machine is being moved from one part of the mine to another.

Mounted upon the extension platform 11 are two castings 12 and 13 which support the transmission mechanism by which the motor 14 is connected to the several auxiliary elements of the machine.

Carried by the casting 12 are the bearings 15, 16, and 17 in which is journaled a transverse shaft 18. Formed as part of the cast.- ing 12 is the lower half of the clutch and gear case. The upper half of the clutch and gear case is formed by the casting 19. The casting 19 carries bearings 20 and 21 in which is journaled the longitudinal shaft'22 having at its forward end a flange shaft coupling 23 by which it is connected with the armature shaft of the motor 14. Se-

' cured to the shaft 22 is a worm 24 which meshes with the worm wheel 25, rotatably mounted on the shaft 18, to which it may be 0 eratively connected by means of the c utch 26 of the well known friction disc type. This clutch is shown in the drawings and need not be described in detail. The disc 27 is provided for applying pressure to i the discs of the clutch and a ball bearing 28 is provided for carrying that pressure.

Rigidlymounted upon the shaft 18, preferably between the bearings 15 and 16, is

a brake wheel 29 which is engaged by the friction band 30 arranged to be controlled by movement of the hand lever 31. The lever 31 is formed integral with the collar 32 loosely mounted on the shaft 18., The casting 12, at points adjacent the bearing provided with a series of inclined teeth 33, and the collar 32 is provided with aseries of oppositely inclined teeth adapted to mesh with the teeth 33. The collar has formed upon it a flange 34 and between this flange and the disc 27 is interposed a ball bearing 28. The surfaces of the teeth are so inclined that when the collar 32 is rotated in a direction to release the brake said collaris forced longitudinally of the shaft 18 and its motion is transmittedthrough the ball bearing 28 to the disc 27 to press to- .gether the discs of the friction clutch lVhen the collar 32. is rotated in the opposite direction, the brake is applied and the clutch released.

Attached to the worm wheel 25, to rotate with it independently of the shaft 18, is a sleeve 36 upon which is loosely mounted the sprocket wheel 37. The sprocket wheel 37 is provided with clutch teeth adapted to mesh with similar teeth on the clutch member 38 which is splined to the sleeve 36'.-

This clutch member 38 can be slid along the sleeve into or out of operative position and is frictionally held against accidental movement in either direction by the spring clip 39. Thesprocket wheel 37 is engaged by an endless chain 40 for a purpose which will be hereinafter set forth.

Carried by the casting 13 are bearings 41 and 42 in which is'journaled a shaft 43 in alignment with the shaft 18. The shafts 18 and 43 are connected together by a jaw clutch coupling one member 44 of which is attached to the shaft 18 and the other member 45 of which is fixed to the shaft 43.

Rotatably mounted upon the shaft 43 is a sleeve 40 extending through the bearing 41 to the hub of the clutch coupling 45. Formed at the end of this sleeve 46 remote from the clutch coupling is a spur-gear 47 'upon the end of which is formed clutch teeth 48 adapted to engagment with corresponding tceth of the sliding clutch member 42), which is splined to the shaft. At the other end of the shaft 43 is rotatably mounted a sleeve 50, which extends through the bearings 42, having on one end a flange 51 provided with clutch teeth to engage the corresponding teeth of the clutch member 49' and at the other end a bevel pinion 52 which meshes with a bevel gear 53 attached to the upper end of the vertical shaft The shaft 54 is'journaled in the bearings 55 and 56 of the casting 13 between which is mounted a sprocket wheel 57 for a purpose which will be hereinafter set forth.

Attached to two lugs 58 of the casting 13 are the stud pins 59 upon which is suspended, by lugs 60, a journal bearing 61 adapted to be rotated in a direction parallel with the length of the truck by the adjusting screws 62. Journaledin the bearing 61 is a shaft (33 to one end of which is attached a spur gear (34, which meshes with the gear 47 of the shaft 43, and to the other end is fixed a sprocket wheel (35 which engages the endless chain (33. The chain 66 passes around a sprocket wheel (37 attached to the axle 5 to drive it to propel the truck. The chain (36 may be properly tensioned by the rotation of the shaft ()3 about the studs 59 by means of the adjusting screws 62. variation of the distance between the centers ef the gears 64 and 47. due to the rotation of the shaft 63 about the studs 59 to The effect the adjustment of the chain 66, is within the permissible variation of the meshing of the teeth of the gears.

Attached to the shaft 43 adjacent the bevel pinion 52 is a spur pinion 68 which meshes with the car 69 attached to the shaft 70. The sha t 70 is journaled in bearings 71 of the gear case casting 72 bolted to the casting 13. Splined to the shaft 70 is a spur pinion 73 adapted to slide into and out of engagement with the spur gear 74. The spur gear 74 has an extension hub 75 surrounding and attached to the sleeve 46. The out-er surface of the hub 75 is finished to form a journal in the bearing 41. .By the gearing above described. the sprocket wheel 65 may be connected directly with the shaft 43 through the gears 47 and 64 and the clutch 49, to propel the truck at a relatively high speed for transportingthe machine from place to place, or it may be connected through the gears 68, 69, 73,74 47, and 64 to propel the truck at a relatively slow speed to feed cutting mechanism into the coal to cut it. It is obvious, however, that the inion 73 must not be in mesh with the gear %4 at the same time that the clutch 49 is engaged with the gear 47, and to pro-- vent such an occurrence I have provided a.

system of interlocking levers for'the manipulation of these parts.

Journaled in apertures of the casting13 isa shaft 76 to the rearward end of which is attached a hand lever 77 by which the shaft may be rocked. This hand lever is provided with a spring cngagethe apertures 79 of thecasting 13 to prevent the accidental movement of the hand lever from either of its three operative positions. Attached to the shaft 76 is a sleeve 80 having two upstanding arms 81 each provided with a notch to engage the lugs of the shifting yoke 82 which engages the clutch 49 to shift it.- To the forward 1 end of the shaft 76 is fixed a crank arm '83, connected to the lower end of the'lock bar 84' to move it vertically. Near the upper end of the lockbar 84 is an aperture 1n the form of a double key hole having a circular part 85 and two .narrow vertical extensions 86. Extending through the key hole is a shaft 87 which is slidably supported in bearings 88 on the casting 72..

The diameter of this shaft 87 is such that it will fill the circular'part of the keyhole and prevent the vertical movement of the lock bar. Formed in the shaft 87 is a circumferential groove 89 of such proportions that when'in position to register with the lock bar 84 said bar will be .free to move vertically. Fixed to the shaft 87 is a shifting yoke 90 which engages the groove in the body of the pinions 73 to cause it to move longitudinally of the shaft 70 with. more ment of the shaft 87. A pin 91 projecting pressed latch 78 adapted to from the shaft 87 affords a handle by which it may beconveniently moved. The proportions of the parts are such that when the clutch 49is in engagement either with the gear 47 or the bevel gear 52 the lock bar 84 will engage the groove 89 to hold the pinion 7 3 out of engagement with the gear 74, and when the clutch 49 is in its central, or neutral position, the shaft 87 will be free to move to shift the pinion 73 into its engagement. When the pinion 73 is in engagement with the gear 74 the lock bar 84 will be held by the body of the shaft 87 against vertical movement and will thereby prevent the engagement of the clutch 49.

Supported for vertical adjustment relative to the base plate 1 is a supporting frame in the form of an annular ring 92, adapted to support the coal cutting mecha nism as will hereinafter appear. To -this ported at their top ends by the bearing plate 97, attached to the upstanding guide members 94, and at their lower end in step bearings formed in the bearing brackets 98 attached to the lower side of'the base plate 1. The three sets of screw shafts and guide members constitute upright supports for the annular supporting frame, and the latter can be adjusted vertically in parallelism,or angularly by suitable rotation of the screw shaft. Mounted for free rotation upon the screw shaft 96 are sprocket wheels 99 which are driven by the chain 100 from the sprocket wheel 57. Idler sprocket wheels 101 and 102 serve to guide the chain 100, the sprocket wheel 102 being mounted in the adjustable support 1023 to afford means for adjusting the tension of the chain 100. Thesprocket wheels 99 as shown in Fig. 13 have formedupon their upper surface clutch teeth 104 adapted to engage with similar teeth on clutch n1en1- bers 105 splined to thescrew shafts. The clutch members 105 are each provided with a groove 106 in engagement with the arm 107 attached to a vertical shaft 108. The shaft 108 extends through the floor plate 1 and is provided with a convenient handle 109 by which the movement of the clutch members 105 may be controlled. In the shaft 108 is fixed a projecting pin 110 which engages the upper surface of the castings 111 to support the clutch members 105 when the handle is in the position shown. \Vhen the handle is turned the pin 110 is brought into alignment with a notch 112 and the &

clutch member can be lowered into engagement with the sprocket wheel. By this mechanism the powerof the motor 14 may be applied to any or all of the adjusting screw shafts to effect the vertical adjustment of the ring 92 and with it the cutting mechanism mounted thereon.

Attached to the ring 92 by stud pivot pins 113 are a plurality of rollers 114 upon the edges of which-rests the circular castihg 115 which constitutes the main base frame of the cutting mechanism. This casting 115 forms a turn table, rotatable about the center of the ring 92 and is held against lateral displacement by the guide rollers 116 which engage the inner surface of the ring. In the outer edge of the turn table casting 115 is formed a series of notches 117. A bracket 118 is secured to the ring 92 and in this bracket is slid-ably mounted a bolt 119 which, when in-its inner position, is adapted to engage the notches 117 to lock the turn table against rotation. 126 is an electric. motor-secured to the underside of the turn table. This motor is connected through the pinion 121 and the spur gear 122 with the horizontal power shaft .123 A vertical power shaft 124 is operatively connected with the shaft 12 by means of a bevel pinion and a bevelgear125.

126 is a horizontal shaft mounted in suitable bearings on the underside of the turn table. This shaft 126 carries a ratchet wheel 127 near its center. Pivot-ally mounted at \ach side of the ratchet wheel 127 are arms 128 between which there is pivotally mounted a pawl 129 which is normally helil in engagement with the ratchet wheel by means of the spring 130. The arms 128 are oscillated. about their pivotal axis by means of a link 131 which is connected therewith by means of a knuckle joint 132, and is connected at its other end to the eccentric strap pressed plunger 188 mounted in a bearing 139 on the turn table casting. 1-10 is a sec,- ond pawl normally engaging the ratchet wheel 127 and held in engagement by the spring 141.

In operation when the shaft 124, together with the eccentric 13-1, -is being continuously rotated. oscillatory movement is given to the arms 12S and the pawl 129. which movement is transmitted to the. shaft 126 by means of the ratchet wheel. The shield 135 serves to hold the awl out of engagement with the ratchet 'wiieel during part of its movement. By varying the position of the shield, the pawl may be held inoperative during a greater or less part of its movement and the rate of rotation of the ratchet wheel 127 and the shaft 126 may be thereby regulated. The pawl 140 serves to prevent, retrograde movement of the ratchet wheel and shaft.

The shaft 126 carries at one end a worm 142 which meshes with the worm wheel 143 fixed to the lower end of the vertical shaft 144. The vertical shaft 144 is journaled in a journal bearing 145 formed in the frame casting 115. To the upper end of the shaft 144 is fixed the driving member 146 of a multiple disc friction clutch, the driven member of which is formed in the hub of the winding drum 147. To the upper flange of the drum is attached a disc 148 through the center of which is threaded a screw 149 adapted to contact with the end of the shaft 1-1-1. The screw 149 is provided with a hand wheel 150 by which it may be rotated to raise or lower the drum relative to the shaft 1-14 and clutch member 146, thereby applyin; pressure to or releasing the friction disc of the clutch. Attached to the drum 147 and windable' thereon is a cable 151 the outer end of which may, if desired, be secured, as shown in Fig. 1, to the vertical stud, or holdor 152, which is provided on a ring 92. Horizontal idler sheaves 153 are arranged in a circumferential series around the turn table. These sheaves serve to guide the cable from the holder 152 tangentially to the edge of the turn table. It will now be apparent that when the cable is connected to the holder 152 and the winding drum is caused to rotate in a winding direction, the winding of the cable will cause the rotation of the turn table about the center of the'ring.

lllounted upon a bracket 154 attached to.

the ring 92 is a vertical guide sheave 155 in alignment with a similar sheave 156 attached to the side angle 2 of the truckframe. Two similar sheaves 157 and 158, are mounted horizontally under the rear end of the truck frame. These sheaves are provided to guide the feed cable 151 for use under special conditions which will be hereinafter fully set forth.

Attached to the turn table 115 is a radially extending bracket 159 having an upwardly extending arm 160 to the top of which is fixed a cutter arm 161, and a downwardly extending arm 162 to the bottom of which is secured the cutter arm'163. In the arms 160 and 162 are formed journal bearings wherein is journaled a vertical shaft 164'to the projecting ends of which are attached the driving sprocket wheels 165 and 166 of the respective cutter arms. Mounted upon the vertical shaft 164, between the arms 160 and 162 is a sprocket wheel 167 which is engagedby theendless driving chain 168. The chain 168 also passes around the sprocket wheels 169 fixed to the upper end of the vertical shaft 124. Through the chain 168 and sprocket wheels 167 and 169 powerfrom the motor 120 is transmitted to the vertical shaft 164.- to actuate the cutting mechanism. The cutter arms 161 and 168 are of a well known construction each consisting of an elongated frame around theedges of which travels a cutter chain 170 provided with .renewable cutter bits adapted to form horizontal ke'rfs 161 and 163 in the coal body. At the forward end of each of'tlie cutter arms is secured a ball bearing 171 upon which is rotatable a sprocket wheel 172 engagedand driven by the respective cutter chains. Extending between and attached to the sprocket wheels 172 is a vertical shaft173 provided with transverse sockets in which are set re.- newable cutter bits 17 4 and constitutes a cutter bar adapted to form a vertical kerf 17 3 in the coal body. The cutter .arms 161- and 163 and the cutter bar 173 constitute a cutting mechanism which when moved trans, versely-of the coal body will form a continuous kerf I coal to completely sever sections 191 thercfrom.

In order to avoid frequent interruptions in the operation of the machine, and its withdrawal from the mine roomafter each successive cut to'permit of the removal or,

the broken down coal, have provided a conveyer which aflt'ord's convenient means for removin the coalv rearward 1y of the machine an loading it into conveniently placed cars for transportation from the mines. This conveyer has a relatively low horizontal portion 175,- resting upon the base plate ofthetruck and extending forvwardly beneath the turntable 115, an inclined. portion 176 "and a 'relativelf high horizontalportion 177 which exten s rearwardly of the machine to discharge the coal into cars I78 conveniently positioned upon themine tracks 8. This conveyer may be of anypreferred type but for the purpose of illustration I have shown a conveyer of thewell known chain and scraper type comprising a pair of endless chains 179 "joined at spaced intervals by cross bars 180 and. adapted to travel over the bottom. plates 181 of the conveyer trough to propel material therealong; The conveyer trough is com osed-j of suitable plates and angles joine together in the manner well known in conveyer practice and need not be'further described at this time. At the forward end of the conveyer the chains 179 pass around across bar 182 fixed in the conveyer frame and at the-rearward end around thecustomary foot shaft.

183 which is provided with the usual devices for adjusting the'tension of the chains.

above, behind, and below the vein i as. above described, the mechanism will. be returned to the right suitable jacks. may be truck frame in any pre erred manner, but 'as their use will vary with local conditionswhich are well understood' by. those engaged tion of t at this time.

.The rearward part" of the'conveyer is ,sup-

strand of the conveyer chains 179 to drive I the conveyer. Mounted upon the projected end of the shaft 186 is a sprocketwheel 188 which is engaged by the driving chain through'which power is transmitted from The side plates-189 of the lower horizontal porthe' motor- 14 to drive the conveyer.

tion 17 5 of the conveyer-constitutes a convenient hopper into which material may be .sho'veled by the operator to be moved along the trough by the chain and scrapers and deposited in the car 178 for transportation from the mine.

, When working on plan, ateach successive operationlthe cutting mechanism is turned to the right hand side ofthe roomand the machine advanced to a suitable positionrelative to the coal face. The supporting ring2is then vertically adjusted to brin the lower cutter arm 163 to the level 0 .the mine floor as illustrated in Fig. 17. The feed'rope 151 -is then drawnout from the w indingdrum 147 passed around the and attachedto the'abutment152, as illustrated in-Fig. 1. The motor 120' is then started to drive the cutting mechanism, and

the hand wheel 150 manipulated to cause the feed'ro e 151 to be wound upon the-drum 147.; T e cuttingmechanism will thus be from ri ht to left-, Cut-13111 .acrescent shaped block ov coal from the V0111; As the cutting coal up into convenientsiae tov be shoveled onto t e conveyer, 175 and by it loaded into the car 178 for removal from the mine. After the removal of the lower" portion of the cutting hand side of the room and the =support1ng ring 92 adjusted vertically to bring the upper cutter arm.161.tofithe level of. the

mine roof as illustrated in Fig. 18. The cuttingt mechanism will again be swung to the le to remove the upper part of the vein, completing the operation as illustrated in Fig; 19. v v

Inorder to hold the machine to its work,

laced against the in the operation of suchmachineadescripem is not thought to be necessary the room "and pillar,

guide sheaves 153 caused to swing throu h a semicircular arc nus In Figs. 20, 21, 22, and 23 I have illustrated a method of operation by which this machine may be used to drive entries or other narrow work. In Fig. 20 is shown the initial position of the machine with the forward end of the cutting mechanism advanced to the right hand rib adjacent the coal face. The turn table is then locked against rotation by the bolt 119 and the motor 120 is started to drive the cutting mechanism, and the auxiliary motor 14 is started and the clutch mechanism manipulated to cause the machine to move bodily forward upon'the track rails 8 to the position illustrated in Fig. 21. \Vhen the cutting mechanism has penetrated the coal to a suflicient depth the turn table is again released and the hand wheel manipulated to wind the feed rope to cause the cutting mechanism to swing to the left to the position illustrated in Fig. 22, after which the turn table is again locked and the truck moved rearwardly along the track to the position shown in Fig, 23 thus completing the cut.

in Fig. 24 is illustrated a method of operating the'machine upon the long wall system. In such a case the machine is initial- 1y advanced to the forward end of the coal -face with the cutting mechanism extending forward. rotated towards the left to make the entering or 'sumping cut. When it has reached aposition at right angles to the coal face the turn table 115 will be locked against further rotation and the feed rope 151 drawn out from the drum 147, carried around the guide-sheaves .155, 156, 157 and 158 and attached to a suitable anchor positioned adjacent the coal face at the rear bf the machine. Upon winding the fee-:1 ..I"6pe ,151 the machine will be moved bodily rearwardly causing the cutting mechanism to sever a section from the long wall face of the vein.

"After the removal of'the lower portion of.

the vein the machine maybe returned to the point of beginning and the upper part removed as above described. Other methods of operation will suggest themselves to persons skilled in the art, but the above ex- 'amples are thought to be sufiicient to demonstrate that the cutting mechanism here described is adapted to be moved either inwardly or outwardlyor laterally in the direction relative to the coal face to complete- 1 sever blocks of material from the body of t e vein;

What I claim is:

1.In a mining machine, the combination with'a supporting base, of cuttin mechanism mounted thereon comprising two spaced apart kerf cutters adapted to form kerfs above and below a section of the mine wall, and a kerf cutter extending between The cutting mechanism is then the inner ends of said spaced apart kerf cutters and having cutter bits arranged to cut a kerf between the aforesaid kerfs when said cutting mechanism is moving either inwardly or outwardly or laterally in either direction relative to the material to be mined.

2.v In a mining machine, the combination with a supporting base, of cutting mechanism mounted thereon comprising two par- 7 cutter bits arranged to cut a kerf extending between said parallel kerfs while said cutting mechanism is moving either inwardly or outwardly or transversely in either direction relative to the materials to be mined. 3. In a mining machine, the combination with a supporting base adapted to be moved towards or from a coal face, of cutting mechanism pivotally mounted thereon comprising two spaced apart kerf cutters adapt ed to form spaced apart kerfs in the mine wall, and a kerf cutter extending between the inner ends of said spaced apart kerf cutters and having cutter bits arranged to cut a kerf between said spaced apart kerfs when said supporting base is moving either inwardly or outwardly or when said cutting mechanism is moving laterally in either direction about its pivot.

' 4. Ina mining machine, the combination with a supporting base adapted to be moved toward or from a coal face, of cutting mechanism pivotally mounted thereon comprising two spaced apart parallel kerf cutters adapted to form parallel kerfs in the mine wall and a kerf cutter extending between the inner ends of said spaced apart kerf cutters and having cutter bits arranged to cut a'kerf between said parallel kerfs when said supporting base is moving either inwardly or outwardly or said cutting mechanism is moving laterally in either direction about its pivot.

5. In a minin machine, the combination with a supportlngbase, of vertically adjustable cutting mechanism pivotally mounted thereon comprising two spaced apart kerf cutters adapted to form spaced apart kerfs in the mine wall, and a kerf cutter extending between the inner ends of said spaced apart kerf cutters and having cutter bits arranged to cut a kerf between said spaced apart kerfs when said supporting base is moving either inwardly or outwardly or when said cutting mechanism is moving laterally in-either direction above its pivot.

6. In a mining machine, the combination with a supporting base, of pivotally mounted cutting mechanism comprising two vertically spaced'parallel elongated cutter base, of pivotally mounted cutting mechani-sm comprising two vertically spaced -parallel elongated cutter arms, cutter chains upon the cutter arms, and a vertical rotary cutter bar extending between the inner ends of the cutter arms and arranged to be actuiited by the cutter chains.

In a mining machine, the combination with a supporting base, of pivotally anounted cutting mechanism comprising a plurality of spaced parallel elongated cut- .ter arms, cutter chains upon the cutter arms,

and a rotary cutter bar perpendicular to said cutter arm extendlng between the inner ends thereof and arranged to be actuated by the cutter chains.

9. In a mining machine, the. combination with a cutting mechanism comprising a plurality of spaced parallel elongated cutter arms. cutter chains upon the cutter arms, and

a rotary cutter bar perpendicular to said cutter arms and extending betwecn'the inner ends thereof and arranged to be actuated by said cutter chains, with means to move said cutting mechanism relative to the material to be mined to sever-blocks of material therefrom.

10. In a mining machine, the combination with cutting mechanism comprising a plurality of spaced parallel elongated cutter arms, cutter chains upon the cutter arms, and a rotary cutter bar perpendicular to said cutter arms and extending between the inner ends thereof and arranged to be actuated by said cutter chains, with means to more said cutting mechanism either inwardly or outwardly or laterally in either direction relative to the material to be mined to sever blocks of material therefrom.

11. In a mining machine, the combination with a cutting mechanism comprising a plurality of spaced parallel elongated cutter arms, cutter chains upon the cutter arms, and a rotary cutter bar perpendicular to said cutter arms and extending between the inner ends thereof and arranged to be actuated by the cutter chains, with means to move said cutting mechanism either inwardlv or outwardly or laterally in either direction relative to the material to be mined to-sever blocks of material therefrom, and means to adjust the cutting mechanism perpendicularly relative to the direction of cut ting movement.

12. In a mining machine, the combination with a wheel supported truck, of a pivotally mounted supporting base, cutting mechanism extending laterally from the supporting base comprising two laterally spaced parallel elongated cutter arms, outter chains upon the cutter arms, a vertical rotary cutter bar extending between the inner ends of the cutter arms and arranged to be actuated by the cutter chains, means to rotate the supporting base relative to the truck, and means to move the truck relative to the material to be mined.

13. In a mining machine, the combination with a wheel supported truck, of a pivotally mounted supporting base, cutting mechanism extending laterally from the supporting base comprising two vertically spaced parallel elongated cutter arms, outter chains upon the cutter arms, a vertical rotary cutter bar extending between the inner ends of the cutter arms and arranged to be actuated by the cutter chains, means to adjust the supporting base vertically, means to rotate the supporting base, and means to move the truck relative to the material to be mined.

In testimony whereof, I aflix my signature.

NILS D. LEVIN. 

